Traditionally high volume cutting of thin gage metals, cardboard, paper, etc. is done with mechanical press die-cutting tools operating at a very high number of hits per minute. This high volume cutting requires expensive dedicated cutting-tools, long setup, and professional knowledge. Laser cutting can replace the traditional mechanical cutting methods and achieve improved quality of the cut-edge as well as eliminating expensive cutting tools. However, the use of laser cutting may affect the productivity as the cutting speed slows down significantly when the thickness of the material (workpiece) to be cut increases.
Common laser cutting processes use lasers such as CO2, YAG or fiber lasers for cutting workpieces of cardboard, paper, plastics, etc. Some of the existing cutting methods use multi-focal optics to create two or more focal-points in different locations along a single optical axis. The plurality of focal points creates a cylindrical energy distribution along the thickness of the workpiece (material) and increases the cutting speed as well as the quality of the cutting edges.
Few existing techniques split a laser beam into a plurality of beams by using of an optical conversion unit. The optical conversion unit can include a first plane reflecting mirror, which comprises two semicircular mirrors, which can be inclined independently of each other, and another reflecting mirror, having a single paraboloidal surface. Other existing method use dual-focus or bifocal lens. Yet other common method uses a multiple focal mirror device, which consists from a plurality of mirror surfaces arranged in serial to the incident light beam. Such construction may enable the creation of a plurality of focal points.